OBSERVATIONS ON COLEOPTERA. 



189 



seems to be general for insects, almost identical conditions being 

 shown by Holmgren in Lepidoptera. 



When the muscle ruptures the break always occurs along the 

 line AB (Fig. 10) level with the surface of the hypodermis, and 

 the long drawn out tendinous ends of each muscle are again in- 



Fn;. II. C. feinorata. Section to show the relation of the muscle fibers immedi- 

 ately after separation from the old cuticula and after the new cuticula has been partly 

 developed. 



corporated into the new cuticula as it is formed, cuticula being 

 developed between the tendons by specialized hypodermal cells 

 and the tendinous ends themselves becoming chitinous. 



These muscle changes, as far as they are related to the hypo- 

 dermis and cuticula behave exactly in Coleoptera as Holmgren 

 has described for the Lepidoptera and the same behavior prob- 

 ably is true for insects in general. 



Cnticula Structures Removed and Replaced at Ecdysis. Con- 

 siderable diversity of opinion prevails as to what and how much 

 of the chitin is removed at ecdysis in insects. I find in L. dcciin- 

 liucata that ecdysis takes place in the following structures: 



i. Body Wall. - - Cuticula entirely removed, including the chi- 

 tinous covering of all hairs, spines and scales, sensory pits and 

 sense organs, including chitinous lenses of both simple and com- 

 pound eyes. 



